Ingot mold



June 18, 1929. F RNE 1,717,504

INGOT MOLD Filed Dec. 51, 1927 Patented June 18, 1929.

UNITED s'rpxres 1,711,504 PATENT OFFICE.

BADOLYFFE FUBNESS, OF JENKINTOWN, PENNSYLVANIA.

moor MOLD.

Application filed December 31, 1927. Serial No. 243,285.

My invention relates to an improvement in ingot molds. A g

It has been reco i'zed that in the casting of an ingot it is desirable to have the metal in the mold cool more rapidly in the lower part of the mold than in the upper part in order that shrinkage of the metal on cooling will be compensated for by a feed of metal from the upper to the lower part of the mold. In order to obtain the metal in the mold from the bottom, it has heretofore been customary to taper the mold outwardly from the bottom, thusafiord- 5 ing a greaterwall thickness and consequently greater'heat absorption capacity at the bottom of the mold than at the top; and at the same time providing for the reception of a greater volume of metal at the top than at the bottom. It is also customary to taper theouter faces of the walls of the mold inwardly from the bottom to decrease the weight of metal in the walls at the top.

Ingot molds as heretofore constructed have ing a progressive solidification from the bottom and complete feeding from the top to compensate for the shrinkage, nor has the ob-- vious device'ot making the taper of the mold 3o iection very great produced thedesired .ef

ect.

In accordance with preferably has a cavity, the contour of the lower portion of which is concave polygonal .in cross section and the upper ortion of which is enlarged by changing t e contour of the polygonal cross section to that of a polygon having because of its shape a less ratio of perimeter to. area than that of thelower portion, which 'may be accomplished .50 by reducing the concavity of the polygonal v contour, changing it to convex, or'by increasing the number of sides up to the production of a circular contour.

Having 'now indicated in a general way the nature and purpose of my invention, I will proceed toa,detailed description of a prethe desired cooling of proved not altogether satisfactory in efiectmy invention, I provlde anmgot mold havmg a metal receiving.-

ferred embodiment thereof, with reference to the accompanying drawings in which:

Fig.1 is a top view of a mold embodying my invention;

Fig. 2 is a vertical sectional view? of the mold taken on line 2-2, Fig. 1.

Fig. 3 is a partial bottom view of the mold.

In the several figures 2 indicates an open bottom mold body having a metal receiving cavity 5 and adapted in use to be placed on a sprue plate, not shown, it being understood. thatmy invention is applicable to molds of other types'than that illustrated,\as for example, closed bottom molds. The lower portion of the cavity '5 is of polygonal contour in cross section, for examplegoctagonal as shown in Figs. 1 and 3, and the walls 4 of the lower portion of-the cavit are preferably made convex, as shown in i s. 1 and 3, in order to prevent bursting, i) ferrostatic pressure from above. The initial skin formed by chilling of the steel against the side of the mold and the contour of the cavity is thus concave polygonal in cross section. The top of the cavity 5 is circular in cross section, as shown at 8, Figs. 1 and 2, while the contour of the upper portion of the cavity adjacent the top varies in cross section resultant from a. rogressive change from polygonal to circu ar contour in the upward extension of'the cavity, as indicated at 10, Figs. 1 and 2.

The walls 4 of the lower portion of the cavity 5, which,'for exam le, is octagonal in cross section, taper outwardly in their upward extension. The walls of the upper portion of the cavity in which the cross sectional contour varies also taper outwardly in their upward extension and to agreate'r degree thando'the walls 4, however, it will be noted that the cavity on its extreme diameters tapers continuously with an unchanged taper from'the bottom to the circular portion, on lines formed at the. juncture of adjacent walls as shown at 6 in the several figures. However, it

will be appreciated that the taper of. the. cavit on its extremediameters maybe varied 1n difi'erent portions of its length with-' V out departing from my invention.

Itwill be understood that it is not essential'that the cross sectional contour of thecavity at the top be circular, since the benefits of my invention may be substantially had by changing the cross sectional contourof the upper portion of the cavity from, for example, a polygon of a certain number of sides to a polygon of an increased number of sides, or

tion, whereby progressive cooling 0 an ingot from the bottom and effective feed of metal from the top to compensate for shrinkage is insured to a degree hitherto unattained.

Havin now fully described my invention,

what I c aim and desire to protect by Letters Patent is': 7

1. An ingot mold. rovided with a metal receiving cavity and having chilling efiect on metal therein decreasing toward the top for-a substantial distance by a gradual change; in a the ratio of perimeter to cross section of the cavity by a gradual change in the contour of the cavity.

2; An ingot mold comprising a mold body provided with a metal receiving cavity, the

cavity being concave polygonal in its lower portion and the concavity being gradually reduced in the upward extension of the mold.-

3. An ingot mold comprising a mold body provided witha'metal receiving cavity, the cavity being concave poly onal in its lower portion and in its upwar extension gradually changing to convex polygonal. H 4 4-. An ingot mold comprising a mold body provided with 'ametal receivingcavity, the

cavity being concave polygonal in-its lower portion and in its upward extension gradually changing to circular.

' 5,. An ingot mold comprising a mold body provided with ametal receiving cavity, the

cavity being concave polygonal in its lower portion and in its upward extension gradually changing to convex polygonal, the change from concave polygonal to convex polygonal being so graduated as to, produce a gradually decreasing chill of metal in the cavity toward the top thereof. f

6. An ingot mold comprising a mold body, provided with a metal receiving cavity, hav-- ing in its upward extension a portion of given polygonal contour and a portion equal to not substantially less than one-third of its length, whichis of difiernt polygonal contour.

7 An ingot mold comprising a mold body provided with a metal receiving cavity, the cavity tapering on its extreme diameter with 'an unchanged taper in its 11 ward extena polygon sion, I having t e contour 0 throughout its lower portion and having a portion of substantial extent adjacent its top of varying polygonal contour incross section at difierent points.

In testimony of which invention, I have hereunto set my hand, at Philadelphia, Pennsylvania, on this 27th day of December, 1927.

RADCLYFFE FURNESS. 

